Natural gas is an important resource as a fuel and is becoming an important resource for upgrading to higher molecular weight hydrocarbons. Natural gas must be treated to meet pipeline or LNG (liquefied natural gas) specifications before transporting to either an end user for combustion as a fuel or to a processing plant for conversion to higher molecular weight hydrocarbons. Natural gas contains a substantial amount of impurities, or contaminants, that require removal. The contaminants include carbon dioxide, water, sulfur compounds, and even some heavy metals, such as mercury.
Processes for treating natural gas are known, and include solvent based systems and molecular sieve based systems. However, the composition of a natural gas stream fluctuates over time, and the amount of contaminants also varies over time. The process of treating natural gas includes designing equipment for treating peak flows of contaminants. This leads to excessive amounts of solvents, and to oversized equipment for the treatment of natural gas.
The improvement in processes for treating natural gas can reduce the cost and energy in generating a natural gas stream that meets pipeline or LNG specifications.